[Ffmpeg-devel] Apple h264 compatibility
Fri Jun 24 12:33:24 CEST 2005
> Gianluigi Tiesi <mplayer at netfarm.it> writes:
> > On Sun, Jun 19, 2005 at 04:00:59PM +0200, M?ns Rullg?rd wrote:
> >> Gianluigi Tiesi <mplayer at netfarm.it> writes:
> >> > I've just tried some apple h264 samples, since the x264 decoder
> >> > is internal to ffmpeg I'm posting here but I could forward the
> >> > directly to x264 ml if needed.
> >> This is the right place. The lavc h264 decoder is entirely separate
> >> from x264, although some of the same people work on both.
> >> > Anyway I've downloaded some great samples from:
> >> > http://www.apple.com/quicktime/hdgallery/
> >> >
> >> > the quicktime decoder is very sloppy I think it need a cray to decode
> >> > the video, but mplayer plays it very fast, the problem is some sort
> >> > incompatibilities but I think they are not so difficult to fix since
> >> > the movie is almost played well, there are some glitches, the debug
> >> > shows some errors for me:
> >> Do all the trailers have those errors, or just some?
> > It really seams that problems comes when the cpu has some difficult
> > to decode the video, serenity_m1080p.mov is almost frozen,
> > but fantastic_four_m420p.mov works fine,
> > wildlifehd works untile the video becomes more complex,
> > also if I move the mplayer window (blocking the decoder thread)
> > a bunch of errors are displayed.
> > Error are the same only values are different, at this point,
> > I think it's not directly a decoder problem, but rather to the part
> > of decoder that should handle dropped frames.
> Mplayer with frame dropping doesn't work with H.264. It appears that
> it discards B frames without decoding them, in the belief that they
> are not used as reference frames. This used to be the case with older
> codecs, but H.264 allows B frames as reference frames. Try without
> frame dropping. If there are still decoding errors, there's a bug or
> an unimplemented feature.
afaik apple's avc encoder doesnt use b-frames as references
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